Make sure all intermediate variables holding mount flags (mnt_flag)

and that all internal kernel calls passing mount flags are declared
as uint64_t so that flags in the top 32-bits are not lost.

MFC after: 2 weeks

1 files changed, 36 insertions, 19 deletions

diff --git a/sys/kern/vfs_mount.c b/sys/kern/vfs_mount.c
index 9100a9c..5fa086c 100644
--- a/sys/kern/vfs_mount.c
+++ b/sys/kern/vfs_mount.c
@@ -72,8 +72,8 @@ __FBSDID("$FreeBSD$");
 
 #define	VFS_MOUNTARG_SIZE_MAX	(1024 * 64)
 
-static int	vfs_domount(struct thread *td, const char *fstype,
-		    char *fspath, int fsflags, struct vfsoptlist **optlist);
+static int	vfs_domount(struct thread *td, const char *fstype, char *fspath,
+		    uint64_t fsflags, struct vfsoptlist **optlist);
 static void	free_mntarg(struct mntarg *ma);
 
 static int	usermount = 0;
@@ -378,10 +378,18 @@ sys_nmount(td, uap)
 	struct uio *auio;
 	int error;
 	u_int iovcnt;
+	uint64_t flags;
 
-	AUDIT_ARG_FFLAGS(uap->flags);
+	/*
+	 * Mount flags are now 64-bits. On 32-bit archtectures only
+	 * 32-bits are passed in, but from here on everything handles
+	 * 64-bit flags correctly.
+	 */
+	flags = uap->flags;
+
+	AUDIT_ARG_FFLAGS(flags);
 	CTR4(KTR_VFS, "%s: iovp %p with iovcnt %d and flags %d", __func__,
-	    uap->iovp, uap->iovcnt, uap->flags);
+	    uap->iovp, uap->iovcnt, flags);
 
 	/*
 	 * Filter out MNT_ROOTFS.  We do not want clients of nmount() in
@@ -390,7 +398,7 @@ sys_nmount(td, uap)
 	 * MNT_ROOTFS should only be set by the kernel when mounting its
 	 * root file system.
 	 */
-	uap->flags &= ~MNT_ROOTFS;
+	flags &= ~MNT_ROOTFS;
 
 	iovcnt = uap->iovcnt;
 	/*
@@ -409,7 +417,7 @@ sys_nmount(td, uap)
 		    __func__, error);
 		return (error);
 	}
-	error = vfs_donmount(td, uap->flags, auio);
+	error = vfs_donmount(td, flags, auio);
 
 	free(auio, M_IOV);
 	return (error);
@@ -520,7 +528,7 @@ vfs_mount_destroy(struct mount *mp)
 }
 
 int
-vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions)
+vfs_donmount(struct thread *td, uint64_t fsflags, struct uio *fsoptions)
 {
 	struct vfsoptlist *optlist;
 	struct vfsopt *opt, *tmp_opt;
@@ -696,9 +704,17 @@ sys_mount(td, uap)
 	char *fstype;
 	struct vfsconf *vfsp = NULL;
 	struct mntarg *ma = NULL;
+	uint64_t flags;
 	int error;
 
-	AUDIT_ARG_FFLAGS(uap->flags);
+	/*
+	 * Mount flags are now 64-bits. On 32-bit archtectures only
+	 * 32-bits are passed in, but from here on everything handles
+	 * 64-bit flags correctly.
+	 */
+	flags = uap->flags;
+
+	AUDIT_ARG_FFLAGS(flags);
 
 	/*
 	 * Filter out MNT_ROOTFS.  We do not want clients of mount() in
@@ -707,7 +723,7 @@ sys_mount(td, uap)
 	 * MNT_ROOTFS should only be set by the kernel when mounting its
 	 * root file system.
 	 */
-	uap->flags &= ~MNT_ROOTFS;
+	flags &= ~MNT_ROOTFS;
 
 	fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK);
 	error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL);
@@ -731,11 +747,11 @@ sys_mount(td, uap)
 
 	ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN);
 	ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN);
-	ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro");
-	ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid");
-	ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec");
+	ma = mount_argb(ma, flags & MNT_RDONLY, "noro");
+	ma = mount_argb(ma, !(flags & MNT_NOSUID), "nosuid");
+	ma = mount_argb(ma, !(flags & MNT_NOEXEC), "noexec");
 
-	error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags);
+	error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, flags);
 	mtx_unlock(&Giant);
 	return (error);
 }
@@ -749,7 +765,7 @@ vfs_domount_first(
 	struct vfsconf *vfsp,		/* File system type. */
 	char *fspath,			/* Mount path. */
 	struct vnode *vp,		/* Vnode to be covered. */
-	int fsflags,			/* Flags common to all filesystems. */
+	uint64_t fsflags,		/* Flags common to all filesystems. */
 	struct vfsoptlist **optlist	/* Options local to the filesystem. */
 	)
 {
@@ -871,14 +887,15 @@ static int
 vfs_domount_update(
 	struct thread *td,		/* Calling thread. */
 	struct vnode *vp,		/* Mount point vnode. */
-	int fsflags,			/* Flags common to all filesystems. */
+	uint64_t fsflags,		/* Flags common to all filesystems. */
 	struct vfsoptlist **optlist	/* Options local to the filesystem. */
 	)
 {
 	struct oexport_args oexport;
 	struct export_args export;
 	struct mount *mp;
-	int error, export_error, flag;
+	int error, export_error;
+	uint64_t flag;
 
 	mtx_assert(&Giant, MA_OWNED);
 	ASSERT_VOP_ELOCKED(vp, __func__);
@@ -1015,7 +1032,7 @@ vfs_domount(
 	struct thread *td,		/* Calling thread. */
 	const char *fstype,		/* Filesystem type. */
 	char *fspath,			/* Mount path. */
-	int fsflags,			/* Flags common to all filesystems. */
+	uint64_t fsflags,		/* Flags common to all filesystems. */
 	struct vfsoptlist **optlist	/* Options local to the filesystem. */
 	)
 {
@@ -1216,7 +1233,7 @@ dounmount(mp, flags, td)
 {
 	struct vnode *coveredvp, *fsrootvp;
 	int error;
-	int async_flag;
+	uint64_t async_flag;
 	int mnt_gen_r;
 
 	mtx_assert(&Giant, MA_OWNED);
@@ -1925,7 +1942,7 @@ free_mntarg(struct mntarg *ma)
  * Mount a filesystem
  */
 int
-kernel_mount(struct mntarg *ma, int flags)
+kernel_mount(struct mntarg *ma, uint64_t flags)
 {
 	struct uio auio;
 	int error;